The 787 Dreamliner passenger airplane’s unsurpassed efficiency and comfort that may make it one of the most coveted airplane models in history, but since its September 2011 debut in the skies, the plane has been more like a nightmare than a dream for manufacturer Boeing.
Battery fires aboard two separate 787 Dreamliners led to all 50 of the planes in service throughout the world being grounded in January 2013. Boeing engineers raced to fix the problem, which originated inside the plane’s lithium-ion batteries, which powered systems traditionally reliant on hydraulics.
On April 19, the Federal Aviation Administration (FAA) approved of Boeing’s battery fix and gave the Dreamliners retrofitted with the new batteries the green light to fly again. Upon the FAA’s approval, aviation regulators in Japan and other nations allowed the repaired airplanes back into service.
On April 27, Ethiopian Airlines became the first carrier to return its 787 to the air with a commercial flight from Addis Ababa, Ethiopia, to Nairobi, Kenya. Other carriers with 787s in their fleets soon followed.
But on July 12, a fire broke out aboard the Ethiopian Airlines Dreamliner while it was parked at London’s Heathrow Airport, forcing the closure of the airport for 90 minutes. That incident mirrored in many ways the Japan Airlines 787 fire in January, which erupted as the plane sat on the tarmac at Boston’s Logan Airport and prompted the worldwide grounding of all 787s.
The Ethiopian Airlines fire triggered more safety reviews of all the aircraft’s components.
The U.K.’s Air Accidents Investigation Branch (AAIB) carried out an investigation and later issued a report, saying “Detailed examination of the (Emergency Locator Transmitter) has shown some indications of disruption to the battery cells. It is not clear however whether the combustion in the area of the ELT was initiated by a release of energy within the batteries or by an external mechanism such as an electrical short.”
Exacerbating the potential ELT problem is its position within the airplane. The mechanism is located in the ceiling space at the upper rear part of the Dreamliner, an area that does “not typically carry the means of fire detection,” the report said.
“Had this event occurred in flight it could pose a significant safety concern and raise challenges for the cabin crew in tackling the resulting fire,” the AAIB explained.
The regulators recommended that the mechanisms be turned off until solutions are found. The devices are used to emit signals that will guide rescuers to the airplane in the event of an accident and are not critical to the safe operation of the aircraft.
Honeywell International, the manufacturer of the ELTs, said it supported the AAIB’s proposal to switch the devices off pending further investigations.